I've been very concerned for you and DH, that you could be asked for $$$$ later this year, when FIL can't pay the charge bill, utilities, taxes, car, etc. Perhaps you could discuss with DH just what he will say if this happens later on.

OP, I'm concerned about this as well. It's fine for you and DH to be on the same page now about how you're not going to give money to FIL for this party. But what about 6 months from now when FIL calls and says "Our fridge just broke. We have to replace it. We have no money because we are paying the line of credit/credit card. Can you help us buy a fridge?" or when poor MIL says "Our furnace went out. We have no heat in the house. Can you buy us a furnace and pay for installation and we'll pay you back later?" Is your DH as convinced that he will then also say "no"?

I think your DH should ask FIL why it's so important that this party be a surprise? If FIL thinks MIL will enjoy it, why isn't he letting her in on the plans? My suspicion is that he knows she wouldn't approve of the expenditure and she would nix it. So he's making it a surprise. But, like others have said, she probably won't enjoy it because she'll be freaking out and worried the whole time about the cost.

The "none of my business" approach comes with an additional layer, I think.

The OP has been asked to help plan this party. She knows that her FIL cannot afford it and the cost of the party will put him in debt. She knows that the party is being planned without her MIL's knowledge, and that her MIL will be both very upset, and share in the financial loss caused by this party.

Even if I didn't tell my MIL, I think I'd be very uncomfortable actually helping him do this. I think I'd go with telling him outright "I'm really not comfortable helping you plan a surprise party that's going to drive you and MIL further into debt and really upset MIL. It's your money and your relationship, and what you do is up to you, but I can't help you with it."

That's staying out of it. Helping plan the party but not saying anything to the MIL isn't really staying out of it.

On a more general note - this could be a really difficult issue in the long term because there is a high probability that financial irresponsibility on the part of the OP's in-laws could effect the OP and her husband. They're retired and on a set income. If they spend beyond their means and the credit comes back to bite them, it can lead to choices like "Do we pay for their utilities, or do we let them go without power so they'll learn their lesson." Saying that it's not your business is one thing. Watching while your elderly parents sink into poverty, or lose their house, or can't buy groceries, or can't afford the care they need - that's something different.

Of course, if your in-laws do end up coming for money for basic necessities, it gives you leverage. If they want the power turned back on, or the groceries funded, they have to pass control of their finances over to you, for example. That doesn't necessarily make for smooth family dynamics, but it can keep you from suffering financial hardship yourself.

After reading all the comments, I would fall pretty firmly on the say nothing to mom side of things. If it were me and any of my parents or in-laws who all have varying degrees of financial responsibility I can't imagine going to the other spouse.

I can see myself arguing with the person who was coming up up with the plans (or at least running all the numbers for them) but unless I actually thought the planner was incompetant to manage their own affairs, I wouldn't try to interfer.

I've been very concerned for you and DH, that you could be asked for $$$$ later this year, when FIL can't pay the charge bill, utilities, taxes, car, etc. Perhaps you could discuss with DH just what he will say if this happens later on.

OP, I'm concerned about this as well. It's fine for you and DH to be on the same page now about how you're not going to give money to FIL for this party. But what about 6 months from now when FIL calls and says "Our fridge just broke. We have to replace it. We have no money because we are paying the line of credit/credit card. Can you help us buy a fridge?" or when poor MIL says "Our furnace went out. We have no heat in the house. Can you buy us a furnace and pay for installation and we'll pay you back later?" Is your DH as convinced that he will then also say "no"?

I think your DH should ask FIL why it's so important that this party be a surprise? If FIL thinks MIL will enjoy it, why isn't he letting her in on the plans? My suspicion is that he knows she wouldn't approve of the expenditure and she would nix it. So he's making it a surprise. But, like others have said, she probably won't enjoy it because she'll be freaking out and worried the whole time about the cost.

This is an issue we are a bit concerned about as well. DH and I are not well off by any means. We are the poster people for working stiffs lol and could very easily be paycheque to paycheque people but we plans well and manage to save a bit here and there. We are by far unfortunately the most financially responsible of the inlaw clan (not tooting our own here it's just a fact) MIL is good with money though but FIL never has been and I know it's due to a lot of planning and taking over of the finances on MIL's part that they are even comfortable at this point. Plus MIL is in must better health than FIL so if you had to peak into your crystal ball it is way more likely that MIL will by far out live FIL. I think MIL realizes that this is likely the future and she will need to be able to support herself. Her mother is 96 and is still not in need of nursing home care.

Plus the inlaws regularly "support" or help out (enable) my SIL but then that's none of my business and another story.

We have our own family to support and I've been firm with DH that extra money that we work hard to save needs to be saved for our family's benefit. The answer in six month's to for help if they come with be NO. FIL can put the "furnace"on the line of credit? That was what they took it out for before MIL retired and could get approve. It was to be for emergencies and large things that went wrong.

Honestly I have to say what puzzles me most about this is that the restaurant is totally ok with a 40 person party and an open menu. Usually restaurant kitchens prefer to stagger dishes - that's why servers don't ticket load (if 3 tables are all sat in their section at the same time they don't take all 3 tables orders at the same time and bring all those tickets into the kitchen at once. They do one table, take in the ticket, then the next table take in the ticket, then the third table - to allow the kitchen time to stagger the preparation). In this case they want 40 meals all to arrive at once - its easier for the kitchen and ultimately going to be better for the customer to have a limited menu the kitchen can prepare for in advance and be ready to bang out in one big go.

I also think a consideration beyond cost is: will MIL enjoy a surprise party? Not everyone does. I adore my DH and was super happy and surprised when he threw me a surprise birthday party... but honestly? He left off a few friends I would have invited if I were involved in the planning (he did ask my BFF to help, but she doesn't know these two friends, and while she knows of them, they slipped her mind), and he didn't have the music I would have preferred, and while I was dressed up because I thought we were going out to dinner, I would have picked a totally different outfit and hair & make-up for a personal party then I did for what I thought was dinner for just the two of us.

So to to me, the financial concerns are valid, and just one more issue is a whole pile of issues.

OP, do you happen to know if his "line of credit" will be a credit card or tied to their house?

I actually do know that it is a secured line of credit on their property

This frightens me, OP, and I bet it does you too. Knowing this, I know exactly what I would do but I am not in your situation. All I want to do right now is send you and your MIL lots of hugs and well wishes.

Frankly, going over everything in the last few posts - there is no way that any of the options we've considered is going to end well.

If FIL overspends so that he can be the generous host - MIL may end up asking "why did you let him do that?" to the OP at some point.

If MIL puts a stop to FIL's grandiose plans because they can't afford it, he'll sulk because he didn't get to throw the party of his dreams (never mind that he could only dream of paying for it.....).

If the OP and spouse pay for anything - it is coming out of monies that they really shouldn't have to spend to support two adults.

If the OP and spouse don't pay for anything - the ILs could end up in financial ruin or near ruin down the line.

SIL and her spouse are unlikely in the extreme to do anything helpful - like insist on a smaller event, help pay for the party, or limit their requests for "help" over the next few months or years while the bill for this one time extravaganza is paid off - whether by MIL & FIL scrimping or whatever happens......

Unless FIL is the one who just bought the 338 million dollar lottery ticket in the USA (and I seriously doubt it) - "by the pricking of my thumbs, something bad this way comes".

If the OP and spouse pay for anything - it is coming out of monies that they really shouldn't have to spend to support two adults.

I think the OP and her husband should make VERY clear that this is not going to happen!! They need to let both FIL and MIL know that they are financially secure only because they plan well, execute their finances well, save well and even then they don't have enough to support another family or even really help out. MIL and FIL seem to be functioning under the delusion that OP and her husband are rolling in cash. They need to have that concept squashed thoroughly and permanently.

And I agree with everything else VorFemme says too. No matter what, this saga is NOT going to have a "happy ending".

His dad was quite open about it being an open menu, everything will be covered and that it is going on the line of credit

He has a plan for payment. So, we are also to assume that he doesn't also have a plan for paying the credit card?

I'm not saying that he's definitely making a financially wise decision. I am saying, it's no one's business.

By completely technical etiquette, I suppose you're right. But immediate family interactions and close friendships are not governed solely by formal and technical etiquette.

You keep bringing up this idea that FIL knows MIL better than the OP and her DH do, and that is just not necessarily true. Heck, it's not even *likely* to be true on the subject of finances, given all the information we have.

My parents have been fighting about money, rather intensely, for some time now. I know my mother better than my father does on a whole variety of subjects. That's just a fact, and one that my mother says often. My parents are nowhere near the tight financial situation the OP's in-laws are in, but if they were I can predict what would happen:

My father would puff out his chest and plan this ridiculousness and feel like he was the benevolent provider. My mother would walk in, immediately be overwhelmed with how much it was costing. She would quickly do mental calculations in her head, run those against their current debt, assets, and income, and within 10 minutes she would be in the bathroom hysterically crying. The party would be over, my mother would feel publicly humiliated and betrayed, my father would be completely confused and feel that no one was properly appreciating his amazingness.

It would be a disaster of epic proportions for which my mother might never forgive my father.

Whatever formal technical etiquette might say, there's no way in hell I'd allow my mother to go through that public humiliation and panic. No way in hell. Because I love her, and she's my mother, and I know her. And if that made my father feel like I was stepping on his toes, so be it.

Because what's more important here? That my father gets to feel like King Kong for all of 5 minutes? Or that my mother not feel publicly humiliated, betrayed, and see her financial stability ruined? That's an easy question for me, and I honestly don't think Miss Manners or Peggy Post gets a say in that.

If I wasn't sure how my mother would respond, I'd keep my nose out of it. And if it was anyone other than my mother, or someone I was similarly **intimately** close with, I'd keep my mouth shut. But for me personally, I know exactly how my mother would feel and react.

If the OP and spouse pay for anything - it is coming out of monies that they really shouldn't have to spend to support two adults.

I think the OP and her husband should make VERY clear that this is not going to happen!! They need to let both FIL and MIL know that they are financially secure only because they plan well, execute their finances well, save well and even then they don't have enough to support another family or even really help out. MIL and FIL seem to be functioning under the delusion that OP and her husband are rolling in cash. They need to have that concept squashed thoroughly and permanently.

And I agree with everything else VorFemme says too. No matter what, this saga is NOT going to have a "happy ending".

They can't very well say that, and then let FIL go off and spend money that is partly MIL's. "Oh, we knew your husband was spending hand over fist, and didn't warn you - but you'll need to cope with mess he made, we're not helping," isn't a great solution.

My ex used to do this all. the. time. "Grand gestures" that would, ultimately become my responsibility to pay for. I did not enjoy them. I got angry and resentful. I wish some friends or family would have encouraged him to not do this, but I don't think they understood our financial situations.

Ten years ago, I had a friend (we've moved and we lost touch gradually) whose husband (now ex-) did that. He couldn't or wouldn't admit to his family that he wasn't rich, so he'd pick up the check at family get-togethers. Knowing that he was going to do that, his siblings and parents would order expensive things off the menu and pig out (based on what my friend would tell me later).

He did have a fairly good job - but he kept spending to the limit of what he was earning - apparently not remembering little things like income tax, property tax, savings for their kids' college funds, and the like......so he'd spend money that should have been set aside. Then complain because SHE wasn't building up the savings accounts......

His dad was quite open about it being an open menu, everything will be covered and that it is going on the line of credit

He has a plan for payment. So, we are also to assume that he doesn't also have a plan for paying the credit card?

I'm not saying that he's definitely making a financially wise decision. I am saying, it's no one's business.

By completely technical etiquette, I suppose you're right. But immediate family interactions and close friendships are not governed solely by formal and technical etiquette.

You keep bringing up this idea that FIL knows MIL better than the OP and her DH do, and that is just not necessarily true. Heck, it's not even *likely* to be true on the subject of finances, given all the information we have.

My parents have been fighting about money, rather intensely, for some time now. I know my mother better than my father does on a whole variety of subjects. That's just a fact, and one that my mother says often. My parents are nowhere near the tight financial situation the OP's in-laws are in, but if they were I can predict what would happen:

My father would puff out his chest and plan this ridiculousness and feel like he was the benevolent provider. My mother would walk in, immediately be overwhelmed with how much it was costing. She would quickly do mental calculations in her head, run those against their current debt, assets, and income, and within 10 minutes she would be in the bathroom hysterically crying. The party would be over, my mother would feel publicly humiliated and betrayed, my father would be completely confused and feel that no one was properly appreciating his amazingness.

It would be a disaster of epic proportions for which my mother might never forgive my father.

Whatever formal technical etiquette might say, there's no way in hell I'd allow my mother to go through that public humiliation and panic. No way in hell. Because I love her, and she's my mother, and I know her. And if that made my father feel like I was stepping on his toes, so be it.

Because what's more important here? That my father gets to feel like King Kong for all of 5 minutes? Or that my mother not feel publicly humiliated, betrayed, and see her financial stability ruined? That's an easy question for me, and I honestly don't think Miss Manners or Peggy Post gets a say in that.

If I wasn't sure how my mother would respond, I'd keep my nose out of it. And if it was anyone other than my mother, or someone I was similarly **intimately** close with, I'd keep my mouth shut. But for me personally, I know exactly how my mother would feel and react.

I think that it all doesn't matter. We're talking about interference in another couples finances and marriage over an anniversary party. I'm sorry, but this couple has been married for 45 years. They are certainly not naive to how they each handle finances, conflict, etc. Surely if FIL's spending habits have not drastically changed in the last few years, MIL knows how he spends, right? Surely she's adult enough to make her own decisions about how she handles it. She's stayed married to this man for almost half a century. How can anyone say that they know her better than him...or him better than her? He might be an incensitive selfish clod, but unless he's somehow forcing her to stay married to him, they've been through this before, and survived. If she has a heart attack over the spending and decides to leave him, then so be it. If they get into a collosal fight over it, then that's the way that it is.

I think that it's fine for the OP and her DH to express concern to the FIL. I think it would have been fine when the MIL asked for advice in the past to give her sound advice on how to work out money issues with FIL in the future. It's inappropriate for anyone (even her family) to go behind FIL's back and 'tattle' to MIL, jump to conclusions about who's really going to pay for it in the long run, and make huge leaps about where their marriage will end up as a result.

No, family dynamics don't always follow strict etiquette rules; however, as hard as it may be to think of your parents fighting, or possibly divorcing, it is not anyone's place to be the relationship hero, making sure that they interfere to avoid all possible future fights and ensure they stay together. Not only that, but it's a bit presumptious for children to think that they know how to save a marriage better than a couple who has more than twice the experience.

I agree with Aeris in that if this were my parents, knowing them as I do and how the evening would likely play out, I would intervene. Not saying it would be polite, but it's what I would do because I think it would be better for everyone in the long run. To me this would be a big enough deal to warrant being rude. But, that is definitely not advice I can dispense to anyone regardless of circumstance. It sounds like the OP and her DH have made their decision, for both the short term and the long term, and good for them. When in doubt staying out of it is definitely the more polite option, IMO.